package com.itheima.stringbuilder;

public class Demo4 {
    public static void main(String[] args) {
        long start = System.currentTimeMillis();
        String s ="";
        for (int i = 0; i < 50000; i++) {
            s += i;
        }
        System.out.println(s);
        long end = System.currentTimeMillis();
        System.out.println(end - start);
    }
}
